* fix issue when first upload fails (fixes#233)
* show debug settings menu item in main activity
* update ETag in local database when a PUT request returns an updated ETag, meaning that
locally created/updated records won't be downloaded from the server immediately after the upload
* force debugging options for resource detection (because there's no way to turn them on until there's an account)
* provide "report issue" button in debug settings
* provide CONTRIBUTING.md, including instructions on how to report issues
* increase socket timeout from 20 to 45 seconds (hopefully fixes#237)
* previous commit: increase total simultaneous connections to 3 (2 per host)
* allow to enter account name at the end of account setup (fixes#13)
* advise user to enter email address as account name (closes#24)
* support for iCal TRANSP (availability free/busy field)
* create better UIDs using iCal4j UidGenerator and Settings.Secure.ANDROID_ID
* better ORGANIZER/ATTENDEE support, but there are big Android issues yet
* various improvements and bug fixes